Control of human toxoplasmosis.

Toxoplasmosis is caused by Toxoplasma gondii, an apicomplexan parasite that is able to infect any nucleated cell in any warm-blooded animal. Toxoplasma gondii infects around 2 billion people and, whilst only a small percentage of infected people will suffer serious disease, the prevalence of the parasite makes it one of the most damaging zoonotic diseases in the world. Toxoplasmosis is a disease with multiple manifestations: it can cause a fatal encephalitis in immunosuppressed people; if first contracted during pregnancy, it can cause miscarriage or congenital defects in the neonate; and it can cause serious ocular disease, even in immunocompetent people. The disease has a complex epidemiology, being transmitted by ingestion of oocysts that are shed in the faeces of definitive feline hosts and contaminate water, soil and crops, or by consumption of intracellular cysts in undercooked meat from intermediate hosts. In this review we examine current and future approaches to control toxoplasmosis, which encompass a variety of measures that target different components of the life cycle of T. gondii. These include: education programs about the parasite and avoidance of contact with infectious stages; biosecurity and sanitation to ensure food and water safety; chemo- and immunotherapeutics to control active infections and disease; prophylactic options to prevent acquisition of infection by livestock and cyst formation in meat; and vaccines to prevent shedding of oocysts by definitive feline hosts

Antarctic Peninsula glaciation patterns set by landscape evolution and dynamic topography

The dimensions of past ice sheets provide a record of palaeoclimate but depend on underlying topography, which evolves over geological timescales by tectonic uplift and erosional downcutting. Erosion during the Pleistocene epoch (2,580 to 11.650 thousand years ago) reduced glacier extent in some locations even as climate cooled, but whether other non-climatic influences impacted the glacial–geological record is poorly known. The Antarctic Peninsula provides an opportunity to examine this issue because of its long glacial history and preservation of remnants of a low-relief pre-glacial land surface. Here we reconstructed both palaeo-surface topography and long-wavelength variations of surface uplift for the Antarctic Peninsula by using inverse analysis that assimilates local topographic remnants with the branching structures of entire modern drainage networks. We found that the Antarctic Peninsula rose tectonically by up to 1.5 km due to dynamical support from the mantle. Glaciological models using the current climate and our palaeotopography show greatly reduced ice extent in the northern Antarctic Peninsula compared with modern, indicating that the onset of glaciation identified at offshore sites reflects tectonic uplift of the topography rather than climatic cooling. In the southern Antarctic Peninsula, however, we suggest the low-relief pre-glacial landscape supported a considerably greater ice volume than the modern mountainous topography, illustrating the influence of erosional sculpting on glaciation patterns

Comparative Chromosome Maps of Neotropical Rodents Necromys lasiurus and Thaptomys nigrita (Cricetidae) Established by ZOO-FISH

This work presents chromosome homology maps between Mus musculus (MMU) and 2 South American rodent species from the Cricetidae group: Necromys lasiurus (NLA, 2n = 34) and Thaptomys nigrita (TNI, 2n = 52), established by ZOO-FISH using mouse chromosome-specific painting probes. Extending previous molecular cytogenetic studies in Neotropical rodents, the purpose of this work was to delineate evolutionary chromosomal rearrangements in Cricetidae rodents and to reconstruct the phylogenetic relationships among the Akodontini species. Our phylogenetic reconstruction by maximum parsimony analysis of chromosomal characters confirmed one consistent clade of all Neotropical rodents studied so far. In both species analyzed here, we observed the syntenic association of chromosome segments homologous to MMU 8/13, suggesting that this chromosome form is a synapomorphic trait exclusive to Neotropical rodents. Further, the previously described Akodontini-specific syntenic associations MMU 3/18 and MMU 6/12 were observed in N. lasiurus but not in T. nigrita, although the latter species is considered a member of the Akodontini tribe by some authors. Finally, and in agreement with this finding, N. lasiurus and Akodon serrensis share the derived fission of MMU 13, which places them as basal sister clades within Akodontini. Copyright (C) 2011 S. Karger AG, Base

Analysis of Canadian and Irish forage, oats and commercially available equine concentrate feed for pathogenic fungi and mycotoxins

Respiratory infections, recurrent airway obstruction (RAO) and exercise induced pulmonary haemorrhage (EIPH) are major causes of poor performance in horses. Fungi and mycotoxins are now recognised as a major cause of these conditions. The most notable fungi are Aspergillus and Fusarium. Fungal spores can originate from forage, bedding and feed and, in turn, these fungal spores can produce a series of mycotoxins as secondary metabolites